Electric stop mechanism



(No Modl.) 3 SheetsSheet 1.

L. MELLETT. ELECTRIC STOP MECHANISM.

No. 463,198. Patented Nov. 17,1891.

3 Sheets8heet 2. L. MELL'ETT.

(No Model.) 3 Sheets-Sheet 3.

L. MELLET T. ELECTRIC STOP MEGHANISM. No. 468,198. Patented Nov. 17,1891

Wm- ESEEE. I E T UNITED STATES PATENT OFFICE.

LEMUEL MELLETT, OF SOMERVILLE, MASSACHUSETTS.

ELECTRIC STOP MECHANISM.

SPECIFICATION forming part of Letters Patent No. 463,198, dated November17, 1891.

Application filed March 21 1890. Serial No. 344,789. (No model.)

To all whom, it may concern:

Be it known that I, LEMUEL MELLETT, of Somerville, in the county ofMiddlesex and State of Massachusetts, have invented certain new anduseful Improvements in EngineStopping Apparatus, of which the following,taken in connection with the accompanying drawings, is a specification.

This invention relates to the class of apparatus employed to effect,electrically and instantaneously, the shutting off of the steam from anengine by means of levers, press-buttons, or like devices located inremote parts of the works and connecting-wires completing an electriccircuit and leading thence to the engine in order to stop its actionimmediately when required.

My present invention is in the nature of an improvement upon thatsetforth in my application for Letters Patent of the United States filedJanuary 22, 1889, Serial No. 297,146, in respect to the combination ofdevices employed in shutting off the steam, and also as to a means forstarting and stopping the engine repeatedly Without disturbing theelectrical cut-01f apparatus, which is at all times ready for operation,though actually needed but rarely. r

My invention also provides a mechanical, electrical, or steam-actuatedbrake applied by the same means to the fly-wheel simultaneously with theshutting off of the steam from the cylinder. duces by more than one-halfthe time heretofore required to actually stop all movement of theengine, shafting, and machinery, and thus tends in a marked degree tothe saving of life'and limb in case of accident. It is obvious that thissimultaneous action of the cutoff and the brake, effected from a remotepoint through the connecting-wires, is-11ot dependent upon the specificform of apparatus employed for either purpose. Hence I do not limitmygeneral claim to the particular de- Vicesherein shown and described.

The drawings represent suitable apparatus for the most speedy stoppingof the engine under both branches of mypresent invention, and illustratethe simultaneous action of the brake and steam cut-oft devices.

Figure 1 shows in elevation and partial sec= tion an enlarged releasingdevice with the This latter improvement re-- two positions of the partsindicated in full and dotted lines. Fig. 2 is a perspective view showingone form of brake apparatus. Fig. 3 is a sectional detail of the same,and Fig. 4 a general View of an engine furnished with my apparatus forcutting off the steam and applying the brake. Fig. 5 is a detail. Fig. 6illustrates the actuation of the cut-01f direct from the governor.

According to my present invention, a weight is released and caused tocut off the steam and to apply a brake to the face of the flywheelwhenever the electrical circuit is completed by touching a press-buttonin any part of building.

A represents a suitable case located in any convenient part of theengine-room and inclosing the weight-releasing mechanism.

B B are magnets, C the vibrating armature, and D D the conducting-wiresconnecting with the battery and extending through the building andfurnished at intervals with push-buttons E or thg like, whereby theelectric circuit may be instantaneously closed when required.

F represents a horizontal lever pivoted at f and having a limitedmovement controlled by aguide and stop Gr. An adjustable weight H maybeapplied to this lever-,if desired. At or near its pivoted end the leverhas a rigid upright arm F, to which is pivoted a latch I, arranged toengage beneath a collar or projection K on a vertically-movable hollowstem L, through which passes the cord M. The stem L is prolongeddownwardly below the case A and furnished with a loading or weight N,formed, preferably, of a series of rings slipped one below another onsaid stem until the desired amount of weight is obtained, the severalsections or rings being supported and connect-ed to said stem by meansof the annular nut O, screwed thereon. Thus the weight N and the stem L,with its collar K and nut O, are upheld by the engagement of the latch Iunder said collar. Suitable guides are furnished forv the verticalmovement of said parts.

Fig. 1 represents in section a tube 1?, in which the upper end of thestem L moves, with a slot through which the latch I reaches to supportthe collar K. The stem is also guided at a lower point by the walls ofthe opening, where it passes through the bottom of the case A, and thebody of the weight N has a tubular guide Q.

R represents a pivoted and spring-pressed brake, the shoe of which isarranged to bear against the face of the fly-wheel when required tocheck and speedily stop its rotation.

The brake is held at a short distance from the face of the wheel bymeans of a latch S, pivoted to the rigid upright arm of a tripping-leverT, upon the outer end of which the weight N strikes to Withdraw thelatch S, when such weight is dropped by withdrawal of the other latch Ifrom position beneath the collar K. The free end of the lever F has adelicate support readily tripped by a single vibration of the armatureO, as will be seen from Fig. 1. The armature is attracted to the magnetsB when the circuit is closed, and this depresses the long arm of a leverU, pivoted at u, and held up, as shown, by a spring V, against the tipof an adj Listing-screw o. The opposite end of the lever U engagesdetachably with an angular catch W, pivoted at the junction of its armsand furnished with a terminal mouth 10, which receives a stud or pinprojecting laterally from the end of the lever F. When the armature isdepressed, it releases the lever F by causing the lever U to bedisengaged from the catch W, which turns on its pivot, and the partsassume the position indicated by dotted lines, thus dropping the weightN and operating the brake and the steam-cut-oif devices. The cord orwire M, which passes through the hollow stem L, by which the weight N issuspended, runs from the case A over a grooved wheel m and down to thethrottle-valve or steam-cut-off valve of the engine, about as indicatedin'Fig. 4:. For convenient application to these outoffs without alteringthe engine, I provide a pulley X, splitin halves, adapted to be broughttogether laterally and secured rigidly upon the stem of thethrottle-valve. The cord M is passed several times around this pulley,and when the weight N is dropped electrically, as herein described, thepull upon the cord M revolves the pulley X and closes the throttlevalve,to the stem of which said pulley is fixed. I sometimes connect the endof the cord M to a lever normally controlled by the governor andactuating a steam cut-off, as in Fig. 6, such lever in the case ofaccident being actuated by said cord and the weight and releasingmechanism described.

The ordinary stopping and starting of the engine need not disturb myattachments at all, they being held in reserve and always ready 'in anemergency. The cord M, which passes around the pulley X on thethrottlevalve stem, has at its opposite end a small Weight Y, sufiicientsimply to keep said cord drawn fairly taut. When the engineer opens orcloses said valve, the cord, drawn by the small weight Y, runs freelythrough the hollow stem L of the main weight N without tripping thelever F and latch I, which support weight, and Without striking thelever T or latch S, which controls the brake. A liftingline Z isconnected to lever F for the purpose of conveniently restoring it toposition afterit has been tripped and without opening the case A. Thetip of the angular catch W is beveled somewhat, to readily pass underthe raised beak of the releasing-lever U.

I claim as my invention' 1. In an engine-stopping apparatus, thecombination of a brake for the fiy-wheel and a cut-off for thesteam-supply, with means for actuating both devices simultaneously froma remote point through an electric circuit, sub stantially as and forthe purpose set forth.

2. In an engine-stopping apparatus, the lever F F and tripping devicesactuated by closing the electric circuit, in combination with abrake forthe fly-wheel, a Weight N, having a hollow stem normally supported bysaid lever, a cord or wire M, passing freely through I said weight andstem, connected at one end with the engine-valve and furnished at itsopposite end wit-h a light Weight Y, for the purpose set forth.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses, on this 11th day of March, A. D.1890.

LEMUEL MELLETT.

IVitnesses:

A. II. SPENCER, JAMES P. PRINCE.

